1. Field of the Invention
The present invention relates to a process for producing a granular composition of ethylenethiourea-chloroprene rubber which is a noble vulcanization-accelerator for chloroprene rubber.
2. Description of the Prior Arts
In the application of chloroprene rubber, especially non-sulfur modified type of chloroprene rubber, ethylenethiourea has been usually used as a vulcanization accelerator. This is different from the application of the other diene type rubbers. Recently, it has been considered that the use of ethylene thiourea causes environmental hygiene problem. Ethylenethiourea is usually in a form of fine powder, and easily scattered in its handling. In the processing of the rubber by a roll type mixer or Bunbury mixer, it causes trouble breathed into body through nostrils. It is necessary to prevent breathing of the dust of ethylenethiourea by operating in the special conditions.
The inventors have started to prevent scattering of the dust and have invented a process for producing a granular composition of ethylenethiourea-chloroprene rubber as a combination of ethylenethiourea with chloroprene rubber.